Core drill



` Sept. 14 1926.

L. S. COPEI-IN CORE' DRILL Filed March 2,3. 1926 Q @f m5, D ma@ W Mw ,4

M Other objects and 'advantages will appearlatente-'d sept'.v la, i926. .A

narran 1 stares PAT LEONARD S. COPELIN, F COMPTUN, CALIFORNIA.

conn

My invention relates to the art of taking cores from oillwells, being more particularly a rotary 'core drill of the type in which an inner-core-receiving 'tube is mounted within an outer barrel. A It is common practice with. core drills of Lthe' character just referred to, to so'construct the same-as to provide replaceable cutting members which `are ordinarily mountedA in the drill head by means of a threaded con-l nection, the power conducted to the cutting members or blade being through such threaded connection which` results, in many instances, in a; breaking of such connection. i5 A further objection to this form 'of mounting the cutting members is that the threaded connection becomes so tight that upon attempting to remove the cutting members, the parts are broken and it is necessary to renew l) such parts. y

One of the `principalobjects of my invention is to provide a rotary core drill/of the type referred-toin which the weight/f, the pipe and tool is directed against the upper l5 end of the cutter head, andthe power transmitted through keys of 'large dimension, thereby eliminating. any strain upon the` threaded connection between the cutter head L and the drill body. which threads perform- 8 0 the sole function o-fholding the cutter head in place, both in lowering the drill into the well and lifting the same from the well.

- A further object of my invention is to so construct the drill body, cutter head and fluid passages in the drill body so that' the circulating luid is directed behind any solid material forming on the cutter head ordinarily referred to as balling up of the cutters) thereby dislddging such Imaterial.`

Another object of my invention iste make the associated parts oit' the core drill of simple form and construction so that the core drill may be readily assembled' or .taken down as may be necessary.V

lhereinafter from the following specification.V

' Referring `to the' drawings which `are illustrative purposes'onlyf Fig; 1 is a vertical sectional view ot a core drill showing an embodiment of my invenfor above the broken line being madeon -a reduced scale for better illustrating the relationof parts.

Fig. 2 is a s1 de elevation of the cutter head.

neun.

Applicationled March 23, 1926. Serial 11o. 96,708.

Fig. 3 is an inverted plan View of the cut' ter head shown in ig. 2. v Fig. 4 is a sectional plan viewon line X,

Flg' 1 i' i i 'y i i The corev drillv comprises "a hollow drill. body 11, interiorlythreaded at its upperendv to. receive a tool -joint 12, into which is threaded-atits upper end, a pipe or tube 13 ormmg'the-onter barrel, such outer barrel varylng in length to suit requirements, the upper vendofsnch barrel 13v being provided with a threaded connection 414, for attach'- ment'to the shown.4

The lowerend of the'jdrill body 11 is reduced in diameter, as indicated at 15, formmg an 4annular fluid-receiving space to be more particularly hereinafter, referred to. Such reduced portion 15 terminates in a circular base or foot 16,.provided on its under face with a transverse slot 17 extending thereacross, suchslot 17 beingfor the purpose ofreceiving keys 18 torni-ed on the upper end of a cutter head 20. The cutter head 20 is bowl shape in outline as clearly shown in Figs. l and 2, and terminatesiat its lower end'in an annular toothed cutter 21-,the teeth 22 of which, in the forni shown, are preferably of the same radial thickness Jfrom the crown of the teeth to the base of the same, so that during the drilling operation the wearing away of such teeth will be substantially the same from the top to the bottom of the teeth. The cutter 21 is primarily a-'trimmer which trims the sidesof the core as v formed, so that the core may pass freely into the core-receiving opening 23 formed inthe cutter head 20.' The cutter head is also pro-` y vided with two sets f'outwardly extending blades 25, and 26, the'blades 25, being vprer'er-f't ably formed with their cutting'edge 27 'ex-"7`y tending slightly below the cutting edge of the. teeth-22, such blades 2 5 curving slightlyI j f rearwardly and upwardly and increasing in 'widt-h to a point slightly below the top face 10D .28pf the cutterl head 20. VThe blades 26 are formed with their cutting edge 30 extending' outwardly and slightly, downwardly from.

the cutter head 20 at a peint/above the teeth 22 forming the`cutter'l21, suc-h blades 26 inmi tion, such view being'broken away, a portion` lt 'is also to be noted, as shown in Fig. 3,

lower end f ot a\ drill pipe, not

at the blades- 25 do not extend routwardly 11o from the cutter head to as great a distance as the blades 26, whereby the cutting edges -of the blades 25 and 26 overlap in their circularcutting path so that the two blades 25 and 26 together cut or drill a hole of proper diameter.

lThe cutter head is supported .on the drill body 11 by means of a sleeve 31, the lower end of which is slightly yreduced and threaded as indicated at 32, such threaded 'portion of the sleeve engaging a threaded ring 33, which is 'shrunk'into a circular recessed portion 34 'of the cutter head 2G, such sleeve 3l and ring 33 resting upon a-shoulder 35, formed by such circular recess just-4` referred to. It is to'be understood that the ring 33 may be dispensed with and threads cut in thehead 20 to receive the threaded lll) " core-receiving Vopening 40, registering with the core-receiving opening 23 of the. cutter head, such opening 40 being shouldered, as indicated at 41, to receive a core trap 42, such core trap consisting of a circular pipe section to which is attached, at their lower ends, a series of dat spring fingers 43, such springs being attachqdin any suitable manner, as by welding or riveting.

The parts just 'described are assembled in the .following manner: the sleeve 31 is threaded into the cutter head 20, the sleeve being then slipped linto the drill body so that the keys 18 on the cutter head enter into the slot 17 formed in the lower Jface of the drill body 1l. The core trap 42 is then kplaced in the sleeve and the lockingl nut, to which' the lower end of the core receiving tube is welded or otherwise attached, threaded onto the upper end of thesleeve.

lt will be understood from the description of the assembly of the parts that the locking nut 37 pulls the cutter head upwardly so i that the upperface of the same 'and the upper face of the keys engage against the corresponding parts on the lower end of the y drill body 11, and that the power transmittedto the cutters is through the keys and the corresponding parts of the drill body.

The upper end of the core-receiving tube is supplied with a valve structure indicated at 50, for the purpose of permitting mud and fluid to be ejected from the top of the corereceiving tube as the core enters such tube.

Provision is made for the purpose of delivering a circulating Huid to the field of cutting operations, such circulating fluid be- 1ving delivered from the drill pipe to the interior of the outer barrel 13, from which it passes down throughk'the central opening 51 in the tool joint 12 to the interior bf the drill lbody 11, a suitable circular chamber 52 being formed therein. This chamber 52 is provided with a series of outlet passages 53,

-which extend downwardly through the drill bodyand'dscharge into the annular space drill body heretofore referred to.

- YIt is to be noted that in this particular the circulating iuid discharged through such openings -impinges on the outer face of the upper endet thegcutter head in such manvner that in the event that the formation being drilled should ball up on the cutter head', that the same would be washed away A15 formed about the reduced portion of the by the eroding action of suchixcirculating lluid. v

I claim as my invention: V

1. A rotary core drill comprising a drill' body having a .central opening and a transversely extending slotfin'its lower face, a cutter head secured to'said body, keys. on said cutter head extending into the slotv in the body, an outer barrelsecured to said body and an 4inner core receiving tube wit inl said barrel.

2. A rotary core 'drill comprising a drill body having a central opening anda transversely extending slot in. its lower face, a cutter head secured to said body, keys on said cutter head extending intov the slot in the body, van outer barrelsecured to said body and an inner core receiving tube with'- in said barrel, said drill body having an annular reduced portion and having passages thereinv arranged to discharge a circulating fluid into said annular reduced portion.`

'3. A rotary, core drill comprising a drill.

versely extending slot in its lower face, a

cutter head,secured to'said body, keys on said -cutter head extending intothe slot in the body and 'an inner core receiving tube within said `barrel, said cutter head having a plurality of cutter blades extending outwardly therefrom and' an annular toothed cutter formed thereon about a core receiving opening formed in said cutter head, the teeth forming said annular cutter being of the same thickness throughout their length.

5. A rotary core drill comprising a drill body-having -a central opening and a transversely extending slot in its lower face, a cutter head secured to said body, keys on ingenio.

in said barrel, said'eult'er head having a plurality ot'v blades formed thereon ot ditl'erent lateral extension and having' cuttingr edges dispos-.ed in dil'ereutplanes and an annular toothed'eutter 'lu'inelon said head about ace'utral eore receiving' opening.

(S. A lrotary eore drill comprising a drill body havlneT a lcentral opening and a transfyersely extending' slot in its ulower tace, a

cutter head secured to said body,` keys .on said cutter head exteudiugj into' theslot in the body, .an outer barrel seeured'to said body andan inner core receiving' tube fwithv in .said barrel, said cutter head having' a plurality ot blades torrned thereon With their (tutt-iin;r edges in dif'fereu-t planes, and an an'- nular toothed 'cutter formed on said head about a central core receiving opening.

7. A rotary cor'e drill comprising' a drill body having' a central opening and a trans- 'verrely extending' slot in itsloiver tace, a cutter head seeuredto said body, keys ou said eut/ter head extendingr into the slot in the body, an outer btu-rel secured to said body and an inner core receiving tube' withn said barrel, said cutter head havino a plurality of blades` 'lornied thereonot' ditlerent lateral extension,y andrwith their vatting,v edges in ditlereut planes, and an annular toothed Cutter formed on said head about a central core receiving opening.

8. A rotary core drill comprising a drillbody havinel a eentfal opening!r extending longitudinally therethroiurh and a transversely extendingv slotin its lower end, a cutter head, keys on said'head tilting; into said slot in the drill body, a sleeve in said drill body threaded into said cutter head. i'neans for securing said sleeve in said drill body, an inner core receiving' tube mounted in said drill body and an outer barrel mounted on'said drill body.

9. A rotarycore'drill coniprisingfa drill body having a central opening extending' longitudinally theretln'olug'h vand a transversely extendingslot in its lower end, a cutter hiad, keys` on said head fitting into said slot in 'the drill body. a sleeve in said drill body threaded into said cutter head, a locking' nut iu said drill body threaded to said sleeve, a core receiving,r tube extending into said sleeve, means Vfor attaching said tube to Said sleeve,- and an outer barrel on said drill body spaced apart lronrsaid tube.

10. A rotary eore drill eonu'irising 'a drill body liaviner a central opening' extending longitudinally therethrough and a transversely extending slot, in its lower end, a cutter head, keys ou said head littine' into said slot in the drill body, a sleeve in said, drill body threaded into said cutter head, means for securing said sleeve in said drill body, a core trap mounted in said sleeve, an

inner core receiving tube mounted in said drill body and aiiouter barrel mounted on said drill body.

11. A rotary Core drill comprising' a drill body having a shouldered central opening extending longitudinally therethrough and a transversely extending' slot in its lower end, a cutter'head having a central core receiving opening` keys -ou uuid cutter head litting' into said slot in the drill body, a Sleeve in said drill body having' its lower end threaded into said cutter head, a locking-nut threaded onto the upper end ot said sleeve seated on the. shoulderwl nortiou of the central ol'ienine' ol' said drill body, a corev reeeiving tuhe'lixed to said locking-` nut, andA an outer barrel mounted on uaid drill body spaced apart, from said core receiving tube.

12. A rotary core drill comprising' a drill body having a shouldered central opening' extending longitudinally therethrough and a vtransversely extending' slot in ils lower end,

a cutter head having' a central core re'feiving opening, keys on Said cutter head fitting.: into said slot. in the drill body, a sleeve in said drill body having; its lower end tlu'eadedinto said cutter head, a locking nut threaded onto the upper end of said sleeve seated on the shouldered portion ot the central opening of said drill body, a core receivingA tube fixed to said locking nut.- and an outer barrel mounted on said drill 'body spaced apart from said core receiving tube, said Glitter head havingY an annular toot-hed cutter 'formed about the core receiving' opening` therein and a plurality ot cutting blades 't'ormed on said cutter-head extending laterally therefrom. A

In testimony whereof. l havehereunto sei; my hand at Los Angeles, California, this 19th day of March, 15126. v LEONARD S. COPELIN. 

